JP2005155673A - Manufacturing method for bearing mechanism, bearing mechanism, motor, and disk driving device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bearing mechanism having excellent shock resistance and slide performance. <P>SOLUTION: A motor attached to a hard disk driving device is provided with the bearing mechanism 4 having a shaft 41 and a sleeve 42 in which the shaft 41 is inserted. The shaft 41 and the sleeve 42 is formed by stainless steel. A surface of the shaft 41 is provided with a plated layer 410 formed by electroless plating with phosphorous concentration of 6% or more and 12% or less and treating by precipitation hardening in the atmosphere of 500°C or more and 700°C or less. Consequently, slide performance of the bearing mechanism 4 having excellent shock resistance can be improved. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a bearing mechanism having a shaft and a sleeve, an electric motor, and a disk drive device.

  2. Description of the Related Art Conventionally, a motor having a bearing mechanism that inserts a shaft into a cylindrical sleeve and rotatably supports the shaft via lubricating oil has been used in various electronic devices. For example, in a hard disk drive that stores various types of information, a disk-shaped recording medium (that is, a hard disk) on which information is magnetically recorded is rotated by a motor, and information is written and read by a head.

  By the way, in such a motor, the shaft and the sleeve are brought into slidable contact directly (that is, with almost no lubricating oil) when starting and stopping or when receiving a large impact from the outside. At this time, if the surfaces of the shaft and the sleeve are formed of the same material, adhesion due to frictional heat at the time of sliding contact is likely to occur. Therefore, in general, the material configuration of the shaft and the sleeve (so-called material system) ) Are different from each other. For example, one of the shaft and sleeve is formed of stainless steel and then subjected to nitriding treatment, and the other is formed of stainless steel and used as it is, while suppressing the occurrence of adhesion while having high wear resistance. A bearing mechanism capable of doing so is configured.

In Patent Document 1, a sleeve having high surface hardness and high shape accuracy is produced by applying nickel phosphorus electroless plating containing 1 to 5 percent phosphorus to the sleeve, and further, fluororesin powder is applied to the shaft. A technique is disclosed in which electroless plating containing 3 to 20 percent and 7 to 15 percent phosphorus is applied to suppress adhesion between the shaft and the sleeve.
JP-A-11-223213

  In recent years, hard disk drives are being used as storage devices for various portable electronic devices, and demands for impact resistance and reliability have become increasingly severe in addition to miniaturization. However, it is difficult for the conventional bearing system in the motor bearing mechanism to further improve the sliding performance related to impact resistance and reliability. Further, although the surface hardness of the sleeve can be increased by the method of Patent Document 1, it is considered that the improvement in impact resistance is not necessarily realized by increasing the hardness.

  The present invention has been made in view of the above problems, and an object thereof is to provide a bearing mechanism having excellent impact resistance and sliding performance.

  The invention according to claim 1 is a method of manufacturing a bearing mechanism, wherein a step of forming a shaft member and a sleeve member, and electroless nickel plating is applied to one of the shaft member and the sleeve member to form phosphorous. A step of forming a plating layer having a concentration of 6 percent or more and 12 percent or less; and a step of subjecting the one member to a precipitation hardening treatment in an atmosphere of 500 ° C. or more and 700 ° C. or less.

  The invention according to claim 2 is the method for manufacturing the bearing mechanism according to claim 1, wherein the one member is formed of stainless steel.

  Invention of Claim 3 is a manufacturing method of the bearing mechanism of Claim 1 or 2, Comprising: Said one member is the said shaft member.

  The invention according to claim 4 is a bearing mechanism comprising a shaft and a sleeve into which the shaft is inserted, and one of the shaft and the sleeve has a phosphorus concentration formed by electroless nickel plating. It has a plating layer of 6 percent or more and 12 percent or less, and further subjected to precipitation hardening treatment in an atmosphere of 500 ° C. or more and 700 ° C. or less.

  A fifth aspect of the present invention is the bearing mechanism according to the fourth aspect, wherein the one of the shaft and the sleeve is formed of stainless steel.

  The invention according to claim 6 is the bearing mechanism according to claim 4 or 5, wherein the shaft has the plated layer.

  The invention according to claim 7 is an electric motor, comprising the bearing mechanism according to any one of claims 4 to 6 and a drive mechanism for rotating the shaft relative to the sleeve. .

  The invention according to claim 8 is a disk drive device, wherein the housing stores a disk-shaped recording medium for recording information, and is fixed inside the casing to rotate the recording medium. And an access means for writing or reading information to or from the recording medium.

  According to the present invention, it is possible to improve the sliding performance of a bearing mechanism having excellent impact resistance, and thus it is possible to improve the reliability of a motor and disk drive device having high impact resistance.

  In the inventions of claims 3 and 6, the bearing mechanism can be easily manufactured.

  FIG. 1 is a diagram showing an internal configuration of a general hard disk drive device 80 to which an electric motor 1 according to an embodiment of the present invention is attached. The inside of the hard disk drive 80 is made a clean space with extremely little dust and dirt by the housing 81. The housing 81 houses a recording disk 82 that is a disk-shaped recording medium, an access unit 83 that writes and / or reads information on the recording disk 82, and the motor 1 that rotates the recording disk 82.

  The access unit 83 includes a head 831 that magnetically writes and reads information in the vicinity of the recording disk 82, an arm 832 that supports the head 831, and an arm 832 that moves the head 831 and the recording disk 82. A head moving mechanism 833 that changes the relative position is provided. With such a configuration, the head 831 accesses a required position of the recording disk 82 in the state of being close to the rotating recording disk 82, and writes and reads information.

  FIG. 2 is a longitudinal sectional view showing the configuration of the disk driving motor 1. The motor 1 includes a rotor portion 2 that is a rotating body and a stator portion 3 that is a fixed body. The rotor portion 2 is rotatably supported with respect to the stator portion 3 by a bearing mechanism 4 having a shaft 41 and a sleeve 42. The

  The rotor portion 2 has a substantially bowl-shaped rotor body 21 that opens to the stator portion 3 side (lower side in FIG. 2), and is formed of stainless steel (for example, SUS303Cu) at the center of the rotor body 21. A shaft 41 having a plating layer on the surface is fixed so as to protrude to the opening side. On the outer peripheral surface of the rotor main body 21, an annular projection 211 is formed on the side of the stator 3, which spreads outward and then bends downward. The inner periphery of the annular projection 211 has a multipolar magnetized circle. An annular field magnet 22 is fixed.

  The stator portion 3 has a substantially disc-shaped base plate 31 that extends in a direction perpendicular to the central axis J 1 of the shaft 41, and a cylindrical portion 311 that protrudes upward is formed at the center of the base plate 31. A substantially cylindrical sleeve 42 that is formed of stainless steel (for example, DHS-1) and into which the free end side of the shaft 41 is inserted is inserted into and fixed to the cylindrical portion 311. In addition, around the cylindrical portion 311, an armature 32 in which a plurality of salient poles provided on an annular core are wound is provided facing the central axis J <b> 1 side of the field magnet 22. The field magnet 22 and the armature 32 constitute a drive mechanism of the motor 1, and the current supplied by a current supply circuit (not shown) connected to the armature 32 is controlled, whereby the rotor portion 2 is connected to the shaft 41. A torque (rotational force) for rotating the stator portion 3 around the center is generated.

  A disc-shaped thrust plate 411 extending around the central axis J1 is formed at the end of the shaft 41 on the free end side. An annular notch 421 is formed on the free end side of the shaft 41 on the inner peripheral surface of the sleeve 42, and the thrust plate 411 is fitted into a disk-shaped space formed by the notch 421. Further, a counter plate 43 that closes the lower opening of the sleeve 42 is provided at the lower end of the sleeve 42, and the counter plate 43 faces the lower surface of the thrust plate 411.

  FIG. 3 is an enlarged view showing the bearing mechanism 4 of the motor 1, and shows only the right side from the central axis J1 in FIG. As shown in FIG. 3, an annular groove 412 is formed on the outer peripheral surface of the shaft 41, and lubricating oil is filled between the shaft 41 and the sleeve 42 above and below the annular groove 412. The radial bearing portions 61 and 62 are configured. In the radial bearing portions 61 and 62, a groove (for example, a herringbone groove) for generating fluid dynamic pressure is formed on the inner peripheral surface of the sleeve 42, and the shaft 41 is perpendicular to the central axis J1 when the motor 1 rotates. Supported in a radial direction. In the radial bearing portions 61 and 62, a fluid dynamic pressure generating groove is formed on at least one of the outer peripheral surface of the shaft 41 and the inner peripheral surface of the sleeve 42, so that the radial bearing utilizing the fluid dynamic pressure is used. The function as a bearing part is fulfilled.

  Lubricating oil is filled between the upper surface (annular surface) of the thrust plate 411 and the surface facing the lower side of the notch 421, and between the lower surface of the thrust plate 411 and the upper surface of the counter plate 43, respectively. Thrust bearing portions 63 and 64 are formed. In the thrust bearing portions 63 and 64, fluid dynamic pressure generating grooves (for example, pump-in spiral grooves) are formed on the upper and lower surfaces of the thrust plate 411, and the shaft 41 is rotated when the motor 1 rotates. It is supported in the central axis J1 direction (also called the axial direction). In the thrust bearing portions 63 and 64, as in the radial bearing portions 61 and 62, a thrust bearing portion using fluid dynamic pressure is formed by forming a fluid dynamic pressure generating groove on at least one of the opposing surfaces. The function is fulfilled.

  Further, as described above, the plating layer 410 is formed on the entire surface of the shaft 41 under specific conditions in the manufacturing process described later.

  Next, the flow of the process for manufacturing the bearing mechanism 4 of the motor 1 will be described. FIG. 4 is a diagram showing a flow of processes for manufacturing the bearing mechanism 4. When manufacturing the bearing mechanism 4, first, a shaft member formed of stainless steel (that is, a member in which a plating layer 410 is formed on the surface in a process described later to become the shaft 41), and a sleeve member (that is, The sleeve 42) is produced, for example, by cutting (step S11). Subsequently, after processing such as surface degreasing, scale removal, and surface activation is performed as necessary, the shaft member is subjected to nickel strike plating to form an underlayer (step S12). When the strike plating is completed, the shaft member is subjected to electroless nickel plating (that is, nickel phosphorus-based electroless plating), and a plating layer having a predetermined phosphorus concentration is formed on the base layer of the shaft member (step S13). .

  Subsequently, a chromate treatment is performed to form a rust preventive film (step S14), and after cleaning, a precipitation hardening treatment is performed on the shaft member to crystallize the amorphous plating layer. (Step S15). In the precipitation hardening process, the atmosphere in the furnace in which the shaft member is placed is heated, for example, to a predetermined temperature described later within 60 minutes, held for about 60 minutes, and then rapidly cooled to about 300 ° C. within 30 minutes. Is done. Then, the shaft 41 having a plating layer formed on the shaft member is inserted into the sleeve 42, and the counter plate 43 is attached to one opening of the sleeve 42 to complete the bearing mechanism 4 (step S16). The strike plating in step S12 and the chromate treatment in step S14 are performed only when necessary depending on the adhesion and corrosion resistance of the plating layer.

  Next, the results of a test for evaluating impact resistance of the hard disk drive device using the motor having the bearing mechanism manufactured by the manufacturing process of FIG. 4 will be described. Table 1 shows the results of a tilt drop test, which is an example of an impact test. In Table 1, “” ”indicates inches. Here, in the tilt drop test, as shown in FIG. 5, in the hard disk drive device 80 in which the motor is driven at the rated rotational speed, the side where the one side surface and the bottom surface of the rectangular parallelepiped housing intersect is defined as the support shaft A1. Whether or not the rotation of the motor is stopped by applying an impact to the hard disk drive 80 by lifting and separating the side A2 where the side surface opposite to the side surface on the side of the support shaft A1 and the bottom surface are raised to a predetermined height H. This is a test for evaluating the impact resistance, and is known as an impact test in consideration of the gyro moment.

  Table 1 shows the result of the tilt drop test for the combination of the phosphorus concentration of the plating layer of the shaft when manufacturing the bearing mechanism and the treatment temperature in the precipitation hardening process, and in the column corresponding to each combination in Table 1 The numbers on the right and left of the upper row indicate the number of samples tested and the number of samples from which the results were obtained, respectively, and the lower row indicates the results of the tests. In the test results, for example, “5” NG ”indicated that the motor stopped when the impact was applied with the height H being 5 inches (127 mm). "7" and vertical OK "indicates that the rotation of the motor does not stop even when an impact is applied with a height H of 7 inches (about 178 mm), and the side A2 Of the motor stops even when an impact is applied from the state where the disk is positioned directly above the spindle A1 (that is, the hard disk drive is set up vertically and the height H is maximum). Indicates that they did not.

  From Table 1, when the precipitation hardening treatment temperature is 600 ° C. and 700 ° C., the result is “7” and vertical OK ”in any case where the phosphorus concentration is 6 to 8%, and excellent impact resistance is obtained. I understand that. Further, even when the precipitation hardening treatment temperature is 500 ° C., “5” NG ”and“ 6 ”NG” are obtained when the phosphorus concentration is 6% and 8%, respectively. Impact properties can be obtained. It is generally known that when the precipitation hardening temperature is too high, sensitization progresses in the plating layer, carbon (C) is generated between crystals, and intergranular corrosion occurs. Has been confirmed to have no such problems.

  On the other hand, paying attention to the phosphorus concentration, 8% is better than 6% at the precipitation hardening treatment temperatures of 350 ° C. and 500 ° C., and it is understood that the impact resistance is improved as the phosphorus concentration is higher. Therefore, in view of an empirical range of phosphorus concentration capable of stably performing electroless nickel plating, it can be said that a phosphorus concentration of 6 percent or more and 12 percent or less is a range in which excellent impact resistance can be obtained.

FIGS. 6A to 6I are diagrams showing the results of X-ray analysis of the plating layer with respect to the combination of the phosphorus concentration of the plating layer of the shaft and the treatment temperature in the precipitation hardening process. Among the peaks shown in the spectra in FIGS. 6A to 6I, the peak marked with a circle is a peak showing Ni ₃ P crystal, and the peak showing X is a peak showing Ni single crystal.

FIGS. 6 (a) and (b), the precipitation hardening treatment temperature is 350 ° C., shows the X-ray analysis results of the phosphorus concentration is 6% and 8%, respectively plating layer, the crystals of Ni 3 _P The peaks shown are 0 and 2, respectively, indicating that Ni ₃ P crystallization has not progressed much.

On the other hand, FIG. 6 (c) and (d) are a precipitation hardening treatment temperature is 500 ° C., the phosphorus concentration indicates the X-ray analysis results for 6% and 8%, respectively, crystals of Ni 3 _P It can be seen that there are three peaks shown, and that the crystallization of Ni ₃ P is relatively advanced.

6 (e) to 6 (g) show X-ray analysis results at a precipitation hardening temperature of 600 ° C. and phosphorus concentrations of 6%, 7%, and 8%, respectively. i) shows the results of X-ray analysis with a precipitation hardening treatment temperature of 700 ° C. and phosphorus concentrations of 6% and 8%, respectively. In each of FIGS. 6 (e) to (i), the crystal of Ni ₃ P It can be seen that there are four or more peaks indicating that crystallization of Ni ₃ P is more advanced. Furthermore, when compared at each precipitation hardening treatment temperature, it can be seen that the crystallization of Ni ₃ P proceeds as the phosphorus concentration increases. These results are in agreement with the results of the tilt drop test in Table 1, and it can be said that the impact resistance is improved as the crystallization of Ni ₃ P progresses.

  FIG. 7 is a diagram showing the relationship between the treatment temperature and the Vickers hardness (hereinafter simply referred to as “hardness”) in the precipitation hardening process when the phosphorus concentration of the plating layer is changed. In FIG. 7, the average value of the hardness at the position on the outer peripheral surface of the shaft 41 corresponding to the radial bearing portions 61 and 62 shown in FIG. 3 is indicated as Rad, and the thrust plate 411 corresponding to the thrust bearing portions 63 and 64, respectively. The average value of the hardness at the position on the upper surface and the lower surface is shown as Axi. The ratio shown before Rad or Axi is the phosphorus concentration of the plating layer.

  As shown in FIG. 7, the hardness decreases approximately linearly as the temperature increases between 350 ° C. and 600 ° C., and the hardness is approximately constant at 600 ° C. and 700 ° C. Therefore, considering the results of the tilt drop test in Table 1, the hardness increases but the impact resistance decreases when the precipitation hardening treatment temperature is low, and the hardness decreases when the precipitation hardening treatment temperature is high. It can be said that the impact is improved. Therefore, at a precipitation hardening treatment temperature of 600 ° C., excellent impact resistance is obtained so that the rotation of the motor does not stop even when the height H is maximized (vertical) in the tilt drop test, and the precipitation hardening treatment temperature is 350. Considering that the hardness decreases linearly between ℃ and 600 ℃, it can be said that sufficiently good impact resistance can be obtained even when the precipitation hardening temperature is about 550 ℃.

  Next, a Falex test, which is another evaluation method for the bearing mechanism 4, will be described. In the Falex test, as shown in FIG. 8, the shaft 41 is disposed between a pair of test pieces (hereinafter referred to as “V blocks”) 91 made of stainless steel, which is a material from which the sleeve is formed. (To be precise, a rod-shaped test piece made of stainless steel having a plated layer as the material of the shaft 41 is sandwiched between the notches 911 formed on the V block 91 so as to face each other), and always supplies lubricating oil. While rotating the shaft 41 at a constant rotational speed (for example, 1200 rpm), one V block 91 is fixed and a load P is applied to the other V block 91 to cause seizure (or adhesion). The sliding performance such as the time until occurrence and the magnitude of the load at that time is examined.

  9 to 13 are diagrams showing various results of the Falex test. 9 and 10 show the relationship between the treatment temperature and the specific wear amount in the precipitation hardening process when the phosphorus concentration of the plating layer is changed, and show the specific wear amount of the shaft 41 and the specific wear amount of the V block 91, respectively. ing. Here, the specific wear amount is a value obtained by dividing the wear rate (= (volume wear amount) / (sliding distance)) by the load P. In FIGS. 9 and 10 and FIGS. 11 to 13 to be described later, the result of a shaft having a plated layer that has not been subjected to precipitation hardening (hereinafter referred to as “untreated shaft”) is denoted by reference numeral 71. The result of a conventional shaft subjected to only nitriding treatment (hereinafter referred to as “nitriding shaft”) is indicated by reference numeral 72.

  As shown in FIG. 9, in the shaft 41, when the precipitation hardening treatment temperature is 500 to 700 ° C. and the phosphorus concentration is 6 percent and 7 percent, the wear resistance superior to the nitriding shaft is realized. Further, the specific wear amount of the V block 91 in FIG. 10 is almost the same at the precipitation hardening treatment temperatures of 350 ° C. and 500 ° C. as compared with the untreated shaft and the nitriding shaft, but is extremely low at 600 ° C. and 700 ° C. It has become less.

  FIG. 11 shows the relationship between the treatment temperature in the precipitation hardening process and the load at which seizure occurs when the phosphorus concentration of the plating layer is changed, and FIG. 12 shows the time until seizure occurs at the process temperature and a predetermined load. Shows the relationship. In FIGS. 11 and 12, the seizure load and seizure time of the shaft 41 are equal at a precipitation hardening treatment temperature of 350 ° C. as compared to the untreated shaft and the nitriding shaft, but at 500 ° C. to 700 ° C. Except in the case of a phosphorus concentration of 7 percent, the higher the temperature, the larger the burn-in load and the longer the burn-in time. In particular, very good results are obtained at 600 ° C and 700 ° C.

  Further, in FIGS. 11 and 12, the seizure load and the seizure time are drastically improved between the precipitation hardening treatment temperatures of 500 ° C. and 600 ° C. Therefore, when the precipitation hardening treatment temperature is 550 ° C., the phosphorus concentration is 7%. Even so, it is believed that better results are obtained than the untreated shaft and the nitridized shaft.

  FIG. 13 is a diagram showing the relationship between the treatment temperature and the friction coefficient in the precipitation hardening process when the phosphorus concentration of the plating layer is changed. Also in FIG. 13, the friction coefficient of the shaft 41 is smaller than that of the nitriding shaft at the precipitation hardening processing temperature of 500 ° C. to 700 ° C. Thus, in the result of the Falex test, it was confirmed that sliding performance superior to the conventional nitriding shaft can be obtained by setting the precipitation hardening treatment temperature to 500 ° C. to 700 ° C.

  As described above, the motor 1 shown in FIG. 2 includes the bearing mechanism 4 having the shaft 41 and the sleeve 42. The shaft 41 has the plating layer 410 on the surface, and the plating layer 410 is formed by phosphorous concentration by electroless nickel plating. Is formed at 6% or more and 12% or less and further subjected to precipitation hardening in an atmosphere of 500 ° C or more and 700 ° C or less. The sleeve 42 is formed of a material different from that of the plated layer 410 of the shaft 41. As a result, the bearing mechanism 4 that suppresses adhesion between the shaft 41 and the sleeve 42 and has excellent impact resistance is realized, and even when a large impact is applied during high-speed rotation of the motor 1. It is possible to prevent the driving of the motor 1 from being hindered. Further, the sliding performance of the bearing mechanism 4 can be improved, and the reliability of the motor 1 can be improved. Further, by using such a motor 1, it is possible to improve the reliability of the hard disk drive device 80 having high impact resistance.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made.

  The structure of the bearing mechanism 4 in the above embodiment is merely an example, and may be appropriately changed depending on the application.

  In the bearing mechanism 4, a plating layer formed by electroless nickel plating and subjected to precipitation hardening may be formed on the sleeve 42. In order to easily manufacture the bearing mechanism 4, it is preferable that a plating layer is formed on the shaft 41 having a simpler shape than the sleeve 42.

  Of the shaft member and the sleeve member, the member on which the plating layer is formed does not necessarily need to be formed of stainless steel, and other materials (for example, phosphor bronze, iron, aluminum, etc.) as long as it is practical. ).

  In the above embodiment, the shaft 41 is fixed to the rotor portion 2 and rotates with respect to the sleeve 42. However, the sleeve 42 is fixed to the rotor portion 2 (or formed integrally) and rotates with respect to the shaft 41. May be.

  In addition to the hard disk drive device 80, the motor 1 can be used for, for example, an apparatus that drives an optical disk, a magneto-optical disk, and other disk-shaped recording media.

It is a figure which shows the structure of a hard-disk drive device. It is a longitudinal cross-sectional view which shows the structure of a motor. It is a figure which expands and shows a bearing mechanism. It is a figure which shows the flow of the process of manufacturing a bearing mechanism. It is a figure for demonstrating a tilt drop test. (A) thru | or (i) is a figure which shows the result of the X-ray analysis of the plating layer with respect to the combination of the phosphorus concentration of the plating layer of a shaft, and the process temperature in a precipitation hardening process. It is a figure which shows the relationship between the process temperature in the precipitation hardening process at the time of changing the phosphorus concentration of a plating layer, and Vickers hardness. It is a figure for demonstrating a Falex test. It is a figure which shows the relationship between the process temperature in the precipitation hardening process at the time of changing the phosphorus density | concentration of a plating layer, and the specific wear amount of a shaft. It is a figure which shows the relationship between the processing temperature in the precipitation hardening process at the time of changing the phosphorus density | concentration of a plating layer, and the specific wear amount of V block. It is a figure which shows the relationship between the process temperature in the precipitation hardening process at the time of changing the phosphorus density | concentration of a plating layer, and the load which a seizure produces. It is a figure which shows the relationship between the process temperature in the precipitation hardening process at the time of changing the phosphorus density | concentration of a plating layer, and time until image sticking arises. It is a figure which shows the relationship between the process temperature in the precipitation hardening process at the time of changing the phosphorus concentration of a plating layer, and a friction coefficient.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Motor 4 Bearing mechanism 22 Field magnet 32 Armature 41 Shaft 42 Sleeve 80 Hard disk drive 81 Housing 82 Recording disk 83 Access part 410 Plating layer S11, S13, S15 Step

Claims (8)

A method of manufacturing a bearing mechanism,
Forming a shaft member and a sleeve member;
Applying electroless nickel plating to one of the shaft member and the sleeve member to form a plating layer having a phosphorus concentration of 6 percent or more and 12 percent or less;
Applying a precipitation hardening treatment to the one member in an atmosphere of 500 ° C. or higher and 700 ° C. or lower;
A method for manufacturing a bearing mechanism, comprising: It is a manufacturing method of the bearing mechanism according to claim 1,
The method of manufacturing a bearing mechanism, wherein the one member is made of stainless steel. It is a manufacturing method of the bearing mechanism according to claim 1 or 2,
The method of manufacturing a bearing mechanism, wherein the one member is the shaft member. A bearing mechanism,
A shaft,
A sleeve into which the shaft is inserted;
With
One of the shaft and the sleeve is a plating layer having a phosphorus concentration of 6% or more and 12% or less formed by electroless nickel plating, and further subjected to precipitation hardening in an atmosphere of 500 ° C or more and 700 ° C or less. Bearing mechanism characterized by having an applied one. The bearing mechanism according to claim 4,
The bearing mechanism is characterized in that the one of the shaft and the sleeve is formed of stainless steel. The bearing mechanism according to claim 4 or 5,
The bearing mechanism, wherein the shaft has the plated layer. An electric motor,
A bearing mechanism according to any one of claims 4 to 6,
A drive mechanism for rotating the shaft relative to the sleeve;
A motor comprising: A disk drive device,
A housing for accommodating a disk-shaped recording medium for recording information;
The motor according to claim 7, wherein the motor is fixed inside the casing and rotates the recording medium;
Access means for writing or reading information to or from the recording medium;
A disk drive device comprising:

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